A fast-paced but short Metroid adventure that should be played by all fans of the series.
Transported back to a Federation medical research station, scientists control the X Parasite by administering a sample of (now extinct) Metroid DNA into Samus' bloodstream. Samus' life is saved but the X Parasite has become infused with her Power Suit and she will never be the same again. Samus is given a new ship and a new mission by the Federation: to investigate the cause of a mysterious explosion on the now lifeless shell of the research station.
Your adventure in Fusion will be directed by the AI of Samus' new ship. You are constantly receiving updates and directions, and so the game proceeds in a much more linear fashion than past Metroid titles. Like during some of her more recent assignments, Samus has lost most of her abilities and must explore the station in order to restore them. Unlike other Metroid games, where Samus finds new equipment to add to her Power Suit, this time around Samus' abilities will be gained by defeating powerful X Parasites and absorbing the biological matter into herself. In this way, you will gradually become more powerful, gaining new abilities as you need them to defeat new threats.
The gameplay of Fusion is easily the best of any 2D Metroid title so far. The controls are very responsive and do exactly what you expect them to do. And while the controls are very reminiscent of Super Metroid, there are some distinct differences. This time around you won't have to hold down a button to run, which is definitely an improvement. Also, Samus is able to grab the edge of platforms when you just miss a jump. These improvements along with a nice implementation of weapon switching (just hold the R button, and fire) make playing Fusion a pleasure.
Graphically, Fusion is very nice. The characters, particularly Samus herself and the larger boss monsters, are very well designed and animated. The environments are very colorful and provide a real feeling of being in an alien world. Like previous Metroid games they span a variety of climates ranging from arctic to inferno, only this time its because of the research station's failing systems. The real stars of the Fusion's graphics are the hand-drawn cut-scenes that drive along the plot. They are crisp and very nice to look at. In the sound department, Fusion is no slouch either. The sound effects for Samus' weapons are all satisfying and the music does a good job of pushing up the tension in the games more difficult moments.
Speaking of the difficulty of the game, on average its a reasonably difficult action game. However, as the game progresses Samus will be pursued by the X Parasite that has mimicked her form to become the SA-X. During these portions of the game your only option is to run for your life! They make for dramatic moments of the game, but they are also incredibly hard, with very little margin for error. And then there's the final boss battle... But hey, it wouldn't be a Metroid game if it weren't hard.
Metroid Fusion is a solid action side-scroller that provides a thrilling but all-too-short (and straightforward) experience. There isn't quite as much exploring to be done this time around, but Fusion is nevertheless a great adventure that deserves to be played by all Metroid fans as well as anyone that enjoys a good action title.